The Evaporative Cooling Effect is a term I learned from an excellent essay by Eliezer Yudowsky that describes a particular phenomena of group dynamics. It occurs when the most high value contributors to a community realize that the community is no longer serving their needs any more and so therefore, leave. When that happens, it drops the general quality of the community down such that the next most high value contributors now find the community underwhelming. Each layer of disappearances slowly reduces the average quality of the group until such a point that you reach the people who are so unskilled-and-unaware of it that they’re unable to tell that they’re part of a mediocre group.

Evaporative Cooling is a dynamic that can apply to both real world and online communities but the affordances of the Internet make it particularly susceptible to Evaporative Cooling.

In a phrase – if your entry costs are low, and you don’t figure out how to keep the muppets and the lunchouts and the free-riders and the parasites from taking over, they will take over.

Nope. ‘Tis a quote from Starship Troopers — the original yarn by Robert Heinlein (which featured troopers each as mighty as whole armies, not the Hollywood ‘booyah!’ interpretation, fun as that was in itself).

I read that book! I love how at the end, after they’ve stitched a ship together out of some wrecks and [tries to remember – defeated some aliens?] the two … no, wait… I am remembering a different Heinlein book – “Space Cadet” I think it was.